1. Field of the Invention
This invention relates to an electronically self-ballasted fluorescent lamp system. More particularly, the fluorescent lamp is substantially planar, i.e., flat, and encloses a low profile housing within an open area inside the fluorescent lamp in which an integral, common housing encloses the ballast and the lamp ends to securely hold the assembly together.
2. Discussion of the Art
Fluorescent lamps are generally economical to operate and thus the energy savings makes them a desirable lamp. One particular type of fluorescent lamp that has found commercial acceptance is referred to as a xe2x80x9c2Dxe2x80x9d lamp in which the lamp is generally shaped like a pair of capital letter Ds disposed in back-to-back, or mirror, relationship. The lamp is an elongated tube bent into the desired 2D shape. Typically, a first housing receives first and second ends of the lamp tube, and a second housing carrying the electronic ballast components is adapted for selective connection to and extends outwardly from one face of the generally planar lamp assembly. Thus, although the tube of the lamp assembly is configured in a substantially planar configuration, and the first housing receiving the lamp ends has a generally planar, low profile, the second or ballast housing extending outwardly from the lamp assembly defeats the advantages offered by the low profile lamp arrangement.
Fixture manufacturers are always searching for an extremely flat or planar lamp product that provides good light output. The system must be low cost and have a high efficiency to optimize the benefits to the consumer. For example, it would be desirable to have a lamp assembly that plugs into an electrical main, while at the same time being held securely in place until such time that the consumer desires to remove the lamp from the fixture, for example, when it reaches the end of its useful life or burns out.
Typically, the ballast is designed to have a life expectancy significantly greater than the lamp tube. However, it then becomes necessary to design the lamp so that it is easily removed without special tools. The design must also assure that good mechanical and electrical connections are made in the original lamp assembly, as well as when a consumer replaces the lamp tube. Accordingly, it is deemed desirable to combine the electronics and the lamp into a common structure so that the entire lamp assembly can be used, handled, and even discarded as a single unit.
A fluorescent lamp assembly includes an integral, common housing that mechanically receives opposite ends of the lamp tube and also encloses lamp electronics therein. The lamp tube has a curved configuration disposed in a single plane. The lamp housing has a low profile that provides good light output while being confined within an inner space of the lamp.
The lamp can be advantageously smaller and more economical since the ballast or electronics need not survive longer than the lamp.
Any wattage lamp can potentially work in an arbitrary fixture socket.
The high frequency electronics ballast allows the construction of a very light weight, economical, high efficiency lighting product with good light output.
The lamp assembly is optimally thin and exhibits a low profile essentially limited only by the lamp thickness because the electronics, lamp, and recess connector all share the same housing and are preferably confined within the planar profile of the lamp.
Moreover, the shape, size, and position of the ballast prevents interference with the lamp ends or tip-offs.